A 25-year-old Brazilian video patent just expired, ending a lingering legal headache for Linux
(www.xda-developers.com)
No.
It has never been a "legal headache", more of a bit of additional work for distro maintainers (to keep codecs separate from the rest of the distro) and a tiny inconvenience for users (they had to click an additional button after installing the distro).
Nowadays it's almost entirely irrelevant. Unless you are in a tiny minority of users who need to play DivX-encoded video (a codec which is 25 years old at this point) for some reason, you don't need to care at all.
Basically, this just made life of a few media horder nerds a tiny bit more convenient. Frankly i shouldn't be typing out a comment this long to even explain it...